CVE-2022-42827: Apple iOS and iPadOS Out-of-Bounds Write Vulnerability

CVE-2022-42827 is an out-of-bounds write vulnerability in the kernel of Apple iOS and iPadOS. An application can abuse it to achieve code execution with kernel privileges, which can fully compromise the device. This matters because kernel-level access lets an attacker bypass normal app sandboxing, persist, and access data or sensors that ordinary apps cannot reach. Confirm all version and configuration details against the vendor advisory before acting.

How it works

The weakness is classified as CWE-787 (out-of-bounds write) combined with CWE-20 (improper input validation). In the kernel, a write operation can be directed past the intended memory bounds when input is not properly checked. An attacker who can run or influence an application on the device can trigger this condition. Successful abuse elevates the application’s capabilities to kernel privileges, allowing arbitrary code execution at that level. Exact trigger conditions and memory layouts are not detailed here; treat the issue as a classic kernel memory-corruption flaw that requires careful validation of any untrusted input reaching the affected path. Do not invent or rely on unconfirmed exploit mechanics—verify behavior against the vendor advisory.

Am I affected? How to find it in your systems

The vulnerability affects Apple iOS and iPadOS devices. These operating systems typically run on iPhones, iPads, and related Apple mobile hardware managed by individuals or enterprises via MDM, Apple Business Manager, or manual inventory. To inventory:

• Query device management consoles or asset databases for all enrolled iOS and iPadOS endpoints and record their current OS build numbers.
• On unmanaged devices, instruct users to check Settings > General > About for the software version, or use Apple Configurator / Apple School Manager / Apple Business Manager reports where available.
• Compare collected versions against the ranges listed in the vendor advisory; only the advisory is authoritative for which builds are vulnerable.

For exploitation signs, look for anomalous kernel panics, unexpected process crashes involving system daemons, sudden privilege-related alerts in MDM telemetry, or unusual application behavior that coincides with elevated system access. Kernel-level activity is often silent; correlate with endpoint detection logs, crash reports, and network indicators of compromise if present. Public detail on specific log signatures is limited, so treat any unexplained kernel instability as a potential indicator and investigate further.

How to remediate

Patch first: apply the updates released by Apple for iOS and iPadOS exactly as described in the vendor advisory. CISA’s required action is to apply updates per vendor instructions. After patching:

• Verify the new build number on a sample of devices to confirm successful installation.
• Re-enable any temporarily disabled features only after confirming the update is complete.
• Harden the environment by enforcing least-privilege app installation policies, requiring code signing, and restricting sideloading or untrusted profiles via MDM.
• Review and tighten kernel-related entitlements and sandbox policies where the platform allows configuration.

These steps reduce the chance that residual or similar memory-safety issues can be abused.

If you can't patch immediately

Until the vendor update can be applied, reduce exposure with compensating controls:

• Segment high-value devices onto restricted networks and limit their ability to install or run untrusted applications.
• Use MDM to enforce app allow-listing, disable unnecessary services, and block installation of apps from unknown sources.
• Apply virtual patching or network-level filtering where possible to block known malicious payloads that target mobile kernels, though this is imperfect for local exploitation.
• Increase monitoring of crash reports, process creation, and privilege-escalation indicators; alert on any kernel panics or unexpected system-level activity.
• Temporarily disable or restrict features that process untrusted input if the advisory identifies them as attack surface (confirm against the advisory).

These measures lower risk but do not eliminate it; schedule the official update as soon as operationally feasible.

If your data may have been exposed

Actively exploited kernel vulnerabilities can lead to full device compromise and subsequent data exposure. If compromise is suspected, isolate the device, preserve forensic artifacts, and follow your incident-response plan. Readers can run a free exposure scan of their email address against known breach data to check whether credentials or personal information have already appeared in public dumps.